Hectograph roll or blanket



Sept. l2, 1939. W- HOSK|NS- JR 2,172,873

HECTQGRAPH ROLL 0R BLANKET Filed Jan. 24, 1958 Patented Sept. 12, 1939 UNITED STATES HEOTOGRAPH ROLL R BLANKET William Hoskins;l Jr.: La Grange, Ill., assignor to Ditto, Incorporated, Chicago, Ill., a corporation of West Virginia Application January 24,1938, Serial No. 186,486 9 claims. (ci. 41 31.6)

'Ihe invention relates to hectograph rolls or blankets which usually comprise a backing and a layer of gelatinous material, the gelatirious material being secured to the backing by a suitable bonding agent, which preferably is of high clarifying power, so that the inks employed in the hectograph process will disappear rapidly.

'I'he backing of a hectograph roll Ais usually paper or cloth, but my invention is limited to 10 this type of backing only to the extent indicated by the appended claims. f Y

To facilitate the disclosure of the invention, referenceis made to the accompanying drawing, which is a cross-section through a hectograph band embodying the invention.

In the drawing the reference character I0 designates the backing of the improved hectograph band, the backing being preferably coated With an ordinary lacquer, such as, for example, py-

roxelin lacquer, if the backing consists of paper or cloth. The lacquer is shown at I I on both sides of the backing sheet, although it is generally customary to lcoat on one side only by means of a roller.

Applied 'to one side of the backing I 0 and adhering to the lacquer coating Il thereon is a l bonding agent l2, to which the gelatinous mass I4 is applied.

. In accordance with this invention, the improved bonding medium l2 is composed largely of glue and adsorbent filler. The preferred composition consists largely of ammonium caseinate, in combination with a colloidal adsorbent material such as bentonite or silica gel, with, if desired, a suitable Water soluble plasticizer such as invert sugar, glycerine, or sulphonated oil. Addition of a tanning agent, such as chrome alum, ferric chloride, potassium dichromate, formaldehyde, tannic acid and the like may also be used to increase the penetration of the bond into the hectograph mass. l

The following example of a preferred embodiment of the bonding agent is given by way of illustration:

. Parts by weight Casein 10 Ammonium hydroxide 5 Bentonite 5 Invert sugar 30 Water 125 In using this composition on a pyroxaline coated cloth I find it advantageous to add say ten' ethylene glycol to provide a better adhesion to the cloth itself. Additional examples of bonding agent formula:

Numerous changes can be made in the above process without departing from the scope of my zo invention and it is understood that the detailed example given above is to be interpreted as illustrating and not limiting the scope of my invention. Other colloidal adsorbent materials than bentonite and silica gel can be used. However, 25 I prefer to use the colloidal clays of which bentonite is a good example.A These materials, particularly when used with casein glues, give an especially satisfactory adhesion. Moreover, the materials appear to act as clarifying agents, aid- 30 ing in the removal of excess dye from the hectograph composition.

What I claim as new isz' 1. A duplicating sheet comprising a flexible backing, a layer of hectograph composition ap- 35 plied to said backing, and means for securing said hectograph composition to said backing come prising an adhesive containing an adsorbent inorganic colloidal material.

2. A duplicating sheet comprising a flexible 40- backing, a layer of hectograph composition applied to said backing, and means for securing said hectograph composition to said backing comprising a colloidal clay.

3. A duplicating sheet comprising a exible 45 backing, a layer of hectograph composition applied to said backing, and means for securing said hectograph composition to said backing comprising bentonite.

4. A duplicating sheet comprising a flexible 50 backing, a layer of` hectograph composition applied to said backing, and means' for securing said hectograph composition to said backing comprising an adhesive containing casein and an adsorbent inorganic material. y

5. A duplicating sheet comprising a flexible backing, a layer of hectograph composition applied to said backing, and means for securing said hectograph composition to said backing com- 5 prising an adhesive containing casein and a co1- loidal clay.

6. A' duplicating sheet comprising a. nexibxe backing, a layer of hectograph composition applied to said backing, and means for securing 10 said hectograph composition to said backing comprising an adhesive containing casein and bentonite.

7. A method of making duplicating sheets comprising the steps of co ating a. backing with a plied to said backing, and means for securing said hectograph composition to said backing comprising'silica gel.

` WILLIAM HOSKINS, JR. 

